Help determining a photographic printing process

[ScottPhotoCo]

What's the best way to determine the type of photographic printing used for a particular image? I have been reviewing a lot of historical images and there is a certain look and feel that shows in some of them that REALLY makes me want to find out and learn the process. I'm guessing it's some type of Platinum and Palladium or Albumen print but I honestly don't know anything about these types of prints. Where can I begin?

Scanning these prints doesn't begin to show what I'm seeing so I'm a bit stuck sharing images here but they are rich tonally with incredible detail and such smooth transitions between tones that it is amazing to me. I have attached 2 scans for reference but they don't do the actual prints any justice at all.




Thanks in advance!


Tim
www.ScottPhoto.co

[Vaughn]

Assuming they are on paper:

First thing to determine is if they have an emulsion or not. Platinum, van dyke, cyanotype, salt, etc, are liquids brushed onto the paper and soak a little ways into the paper.. So if the image is in the paper rather than on the paper, it is one of these types of processes.

Silver gelatin, carbon, albumen are processes that contain the light sensitive chemicals in an emulsion that sits on top of the paper. Not carbon -- carbon does not fade or darken like the top image has.

[ScottPhotoCo]

Assuming they are on paper:

First thing to determine is if they have an emulsion or not. Platinum, van dyke, cyanotype, salt, etc, are liquids brushed onto the paper and soak a little ways into the paper.. So if the image is in the paper rather than on the paper, it is one of these types of processes.

Silver gelatin, carbon, albumen are processes that contain the light sensitive chemicals in an emulsion that sits on top of the paper. Not carbon -- carbon does not fade or darken like the top image has.

Thanks Vaughn!

These both are on paper but I'm not sure how to tell if they're on or in the paper. Please forgive my lack of knowledge, I am new at this part.

The only other potentially identifying element perhaps is a slight shine to parts of the image. I assume that this means the presence of silver? On the image of the couple it is most prominent around the edges where it looks like it was shielded by a frame or something? And on the child's portrait, if you angle it slightly you can see the metallic looking shine in some areas. Does this help?


Tim
www.ScottPhoto.co

[ridax]

Of course no one can be positively sure just looking at jpegs but still I'd bet ten to one on those being Matt Collodion POP, perhaps Platinum toned.

Most of the 100-year-old collodion prints look like new today as collodion is a much better image protector then gelatin (to say nothing of albumen which is a problem in itself) but alas those fascinating prints have poor chances to be seen in another 100 years as nitrocellulose is notorious for its inability to last more then about 150 years at best. Then, those emulsions just turn into a mess of tiny flakes that fall off the paper.

Gelatin POP prints do not behave like that but the images on those fade a lot faster...

[ScottPhotoCo]

Of course no one can be positively sure just looking at jpegs but still I'd bet ten to one on those being Matt Collodion POP, perhaps Platinum toned.

Most of the 100-year-old collodion prints look like new today as collodion is a much better image protector then gelatin (to say nothing of albumen which is a problem in itself) but alas those fascinating prints have poor chances to be seen in another 100 years as nitrocellulose is notorious for its inability to last more then about 150 years at best. Then, those emulsions just turn into a mess of tiny flakes that fall off the paper.

Gelatin POP prints do not behave like that but the images on those fade a lot faster...

Ok, this is pretty fascinating and definitely a process I hadn't heard of previously. I need to look deeper into this. Thanks for the information!


Tim
www.ScottPhoto.co

[Andrew O'Neill]

Do you know when they were printed? They could very well just be gelatin silver contacts. Can you see if the emulsion has lifted slightly from the paper?

[ScottPhotoCo]

Do you know when they were printed? They could very well just be gelatin silver contacts. Can you see if the emulsion has lifted slightly from the paper?

Andrew,

There is no lifting at all on any of the images. If I had to hazard a guess of when they were printed, sometime between 1910-1930? But that is a total guess.

[ridax]

Yes I also can't exclude the possibility of these prints being gelatin though I still believe more likely its collodion. Anyway, I'm pretty sure further online speculation would not bring any definite answer. Go ahead, test them. Take a needle or an old-fashioned pen and with those, put tiny droplets of liquids onto the prints' corners. Acetone will dissolve collodion but not any other known photo print binder. Water will swell gelatin but not collodion.

Reports appreciated.

[SergeiR]

I have quite a few like that in my family album (late 1800s, early 1900s) and they all are silver prints, to be honest. Paper ranges in them quite a bit, from very weird textured one(then again i remember printing on ancient stock of something similar when i was about 13 years old in 80s) to just flat one. All quick thick , some are mounted, some arent. But all of ours that were survived were made in Russia pre-/post- revolution. Other sides of my family didn't get to keep theirs, so i dont know if process was much different for Poland, France and Sweden back then.

[redbird]

This may well help you...
http://www.getty.edu/conservation/pu...ons/atlas.html
there's quite a bit of info about historical processes in the preservation community. If this isn't in depth enough there is is book on historical photographic processes here
https://www.imagepermanenceinstitute...s/publications
scroll down to identification and care of photographic processes.
Hope this helps.
M